液液萃取-气相色谱法测定尿中磷酸二甲酯

Determination of dimethyl phosphate in urine by liquid-liquid extraction-gas chromatography

目的 研究近期低水平接触速灭磷、久效磷人员生物检测指标-尿中磷酸二甲酯的气相色谱法,以对暴露人群健康的长期影响及评估提供有效的检测分析方法。方法 液液萃取浓缩尿样中的磷酸二甲酯,之后在氮气保护下,使用五氟溴苄进行衍生化反应,经程序升温后,对磷酸二甲酯衍生物的浓度进行检测。结果 尿中磷酸二甲酯衍生物的工作曲线在0μg/L~985μg/L浓度内呈线性关系,线性良好(r=0.995 3),检出限为2.5μg/L;高、中、低浓度磷酸二甲酯尿样精密度实验,相对标准偏差均<10%;干扰实验中,另3种二烷基磷酸酯衍生物分离较好,不对磷酸二甲酯衍生物的检测产生干扰;样品-20℃可保存1个月,损失率<10%。结论 配备氮吹仪及火焰光度检测器即可检测尿中磷酸二甲酯,适合较市、县级科研、事业单位的检测应用环境,适用于低剂量接触速灭磷、久效磷的人员的尿中的代谢产物的含量检测。

Objective This paper aims to develop a gas chromatographic method for the detection of urine dimethyl phosphate, a biological indicator for people exposed to low level mevinphos and monocrotophos recently, in order to provide effective detection and analysis method for long-term health effects and assessment of exposed populations. Methods After liquid-liquid extraction of dimethyl phosphate in concentrated urine samples, pentafluorobenzyl bromide was used for derivatization under nitrogen protection, and the concentration of dimethyl phosphate derivatives was detected after temperature program. Results The working curve of dimethyl phosphate derivatives in urine showed a good linear relationship in the range of 0 μg/L-985 μg/L(r=0.995 3), and the detection limit was 2.5 μg/L. The relative standard deviation in the precision test of urine samples with high, medium and low concentrations of dimethyl phosphate was less than 10%. In the interference test, the other three dialkylphosphate derivatives were separated well and did not interfere with the detection of dimethyl phosphate derivatives. The samples could be stored for 1 month at-20 ℃, and the loss rate was less than 10%. Conclusion The nitrogen blower and flame photometric detector can be used to detect dimethyl phosphate in urine, which is suitable for the detection environment of scientific research and public institutions at city and county levels, and it can be used for the determination of metabolites in urine of people exposed to low-dose mevinphos and monocrotophos.